[manny_m]

I have an 05 Mustang V6, just installed a K&N intake system and the Flowmasters American thunder dual exhaust, no H or X pipe just straight back but did not delete the Cat converter, do any of guys know how much rwhp I gained?

[stlwagon]

I'd say maybe 12-15... Add a tune and you'd bump that number to possibly 25.

[manny_m]

Originally Posted by stlwagon

I'd say maybe 12-15... Add a tune and you'd bump that number to possibly 25.

what tuner should i use though?

[mrjimmy]

well I have an SCTxcalibrator2. You might want to look at bamachips.com they have pretty good tunes as wel as VMP.
both are right up there.
the xcal tuner was very easy for me to use,loading new tunes on it.

[GT speeder13]

+1 sct x-cal2 tuners are very easy to use. there are a few good tuners out there. Brenspeed, Evolution Perfomance and Bamachips! tuner will make the world of a difference...

[zenflow]

+1 SCT Xcal2, you'll get more out of that intake with a proper tune made for it. As far as exhaust goes, you gained about 10 from that alone whether it is dual or single really doesn't matter, you only gain about ten just from removing that stock muffler and replacing it. I know I say ONLY ten, but that's actually a pretty good gain for just changing the muffler.